Move to makefile for AVIF

codecs/avif/dec/avif_dec.cpp

@@ -0,0 +1,59 @@
+#include "avif/avif.h"
+#include <emscripten/bind.h>
+#include <emscripten/val.h>
+
+using namespace emscripten;
+
+class RawImage {
+public:
+  val buffer;
+  uint32_t width;
+  uint32_t height;
+
+  RawImage(val b, uint32_t w, uint32_t h) : buffer(b), width(w), height(h) {}
+};
+
+RawImage decode(std::string avifimage) {
+  // point raw.data and raw.size to the contents of an .avif(s)
+  avifROData raw;
+  raw.data = (uint8_t *)avifimage.c_str();
+  raw.size = avifimage.length();
+
+  avifImage *image = avifImageCreateEmpty();
+  avifDecoder *decoder = avifDecoderCreate();
+  avifResult decodeResult = avifDecoderRead(decoder, image, &raw);
+  // image is an independent copy of decoded data, decoder may be destroyed here
+  avifDecoderDestroy(decoder);
+  if (decodeResult != AVIF_RESULT_OK) {
+    return RawImage(val::null(), -1, -1);
+  }
+
+  // Convert to interleaved RGB(A)/BGR(A) using a libavif-allocated buffer.
+  avifRGBImage rgb;
+  avifRGBImageSetDefaults(&rgb, image); // Defaults to AVIF_RGB_FORMAT_RGBA which is what we want.
+  rgb.depth = 8; // Does not need to match image->depth. We always want 8-bit pixels.
+
+  avifRGBImageAllocatePixels(&rgb);
+  avifImageYUVToRGB(image, &rgb);
+
+  // Image has been converted to RGB, we don't need the original anymore.
+  avifImageDestroy(image);
+
+  // We want to create a *copy* of the decoded data to be owned by the JavaScript side.
+  // For that, we perform `new Uint8Array(wasmMemBuffer, wasmPtr, wasmSize).slice()`:
+  auto result = val(typed_memory_view(rgb.rowBytes * rgb.height, rgb.pixels)).call<val>("slice");
+
+  // Now we can safely free the RGB pixels:
+  avifRGBImageFreePixels(&rgb);
+
+  return RawImage(result, rgb.width, rgb.height);
+}
+
+EMSCRIPTEN_BINDINGS(my_module) {
+  class_<RawImage>("RawImage")
+      .property("buffer", &RawImage::buffer)
+      .property("width", &RawImage::width)
+      .property("height", &RawImage::height);
+
+  function("decode", &decode);
+}